After some more experiments by manually sending AT commands over terminal software i found out that it works very simple.
First preset your BG95-G for AUTOCONNECT by the following commands, that work with Vodafone Germany
AT+NCONFIG=AUTOCONNECT,TRUE
AT+NCONFIG=CR_0354_0338_SCRAMBLING,TRUE (depends on your carrier?)
AT+NCONFIG=CR_0859_SI_AVOID,FALSE (depends on your carrier?)
AT+NBAND=20 (depends on your country and carrier!)
AT+CGDCONT=0,“IP”,“nb.inetd.gdsp” (Vodafone, “0” is belonging to AUTOCONNECT)
AT+COPS=0
After the “AT+NRB” reset command these preferences are stored in the NV-RAM of the BC95-G and used for AUTOCONNECT at startup.
Next you see the typed in commands an the response:
at+cfun=1
OK
AT+QMTOPEN=0,"api.wia.io",1883
OK
+QMTOPEN: 0,0
AT+QMTCONN=0,"xyz","d_sk..."
OK
+QMTCONN: 0,0,0
AT+QMTPUB=0,0,0,1,"devices/dev..."
{"name":"NB-IoT"}
Ctrl+Z
OK
+QMTPUB: 0,0,0
AT+QMTPUB=0,0,0,1,"devices/dev_..."
{"name":"NB-IoT"}
Ctrl+Z
OK
+QMTPUB: 0,0,0
Hint: you have to use the "d_sk..." and "dev..." of your device